Current collector for electric vehicles



J 1930- J. F. DE TdvA os 1,744,622

CURRENT COLLECTOR FORELECTRTG VEHICLES Fi July 1 1925 1 3 Sheets-Sheet 11; ve nfar:

71 211 24.5 Z361 er 0 ZZva fra;

Jan. 21; 1930. J. F. DE TcSvARos I 1,744,622

CURRENT COLLECTOR FOR ELECTRIC VEHICLES Filed July 1'7, 1925 3Sheets-Sheet 2 -fwn/en/ar;

z jjoi Zi sa Zer 0 6 791/6170;

Jan. 21, 1930. J. F. DE TvARos 1,744,522

CURRENT COLLECTOR FOR ELECTRIC VEHICLES Fi y 1925 5 Sheets-Sheet 5 f 3&9

Je T va vos AZ'Zorwey Patented Jan. 21, 1939 UNHTE STATES PATENT FFICECURRENT COLLECTOR FOR ELECTRIC VEHICLES Application filed. July 17,1925, Serial No. 44,298, and in Hungary July 23, 1924.

My invention relates to sliding current collecting shoes for electricvehicles of the type having a flat contact surface of substantial extentin the direction of the trolley wire,

pivotally mounted on the trolley frame or pole and intended to be usedon frames arranged at an acute angle to the trolley wire. The object ofthe invention is to secure not only a perfect contact along the wholelength of the contact surface of the shoe collector at any angle of theframe, but also a practically uniform distribution of the contactpressure over the whole contact surface in either travelling directionafter the trolley frame has been tilted into the position correspondingto the travelling direction.

In the annexed drawing 1 have shown several embodiments of the trolleyshoe according to my invention in sectional elevations.

Fig. 1 shows an eccentrically pivoted double-faced shoe.

Figs. 2 and 3 show modified forms of shoes.

Fig.4 shows a centrally pivoted shoe with an eccentric balancing weightlodged therein.

Figs. 5 and 6 show eccentrically pivoted shoes with internal springs.

Fig. 7 shows an eccentrically pivoted threefaced contact piece or shoe.

Fig. 8 shows a centrally pivoted doublefaced shoe controlled by aweighted lever.

Figs. 9 and 10 show two forms of centrally pivoted single-faced shoescontrolled by means of a weighted lever.

Figs. 11 and 12 show two forms of positively guided adjusting mechanismfor singlefaced shoes.

Fig. 18 is an enlarged front View of the shoe represented in Fig. 1, andshowing its mounting on the frame or pole.

Fig. 14 is a plan view of the shoe proper.

Fig. 15 is a fragmental detail view, on a still larger scale and showingthe connection between the shoe and the frame or pole.

With reference to Fig. 1, k is the collector frame or pole pivotallyconnected at Z to the trolley base of the car or the top joint of apantograph trolley frame. a is the contact body or shoe which ispivotally journaled on the hollow or tubular shaft 0. o is the trolleywire. Arrow 2' indicates the direction of travel of the car. The springspressing the frame 76 and the contact body a towards the trolley wire,are not shown. B is the resultant of this pressure and of the frictionacting at the contact surface.

The arms of frame is are hollow, as shown in Figs. 13 and 15, and theends 2 of shaft 0 are inserted in the ends of the frame arms andsuitably secured therein, as by means of screws 4, 4 which arethemselves prevented from becoming loose by wires 5 that are passedthrough holes 9 formed transversely through the screw heads. Theaforesaid shaft ends 2 are slightly bent and are provided with metalfilling plugs 3.

In the constructions hitherto known, the resultant R had to pass throughthe pivot axis 0 in order to secure the balance of the shoe andtherefore could not intersect the contact surface a, at its center (Z.Hence the pressure was greatest at the front edge of the contact surfaceand diminished towards its rear edge, thereby subjecting the front edgeto a premature wear.

According to my invention I secure uniform distribution of the pressurethroughout the whole length of the contact surface, while at the sametime allowing the use of the shoe on a trolley frame inclined in eithertravelling direction, these results being obtained by utilizing aturning moment to lower the front edge of the shoe in either travellingdirection.

According to Fig. 1 this turning moment is attained by the use of a shoeat having two counterpart working faces 0 and a and by arranging thepivot shaft or axis 0 at an equal distance from both working surfacesat, and a viz in the horizontal middle plane 00m of the shoe and at oneside of the centre of gravity G, so that the pressure resultant R whichintersects the eccentric pivot axis 0 also intersects the workingsurface a, in the vertical middle plane g g at d. If the collector isremoved from the trolley wire into the position shown in dotted lines,the shoe will assume, owing to the eccentricity of its centre ofgravity, a vertical position. If the shoe is brought again'into theworking position, the edge nearer to the pivot axis 0 will come firstinto engagement with the trolley wire. Owing to the circumstance thatthe shoe a describes an arc in rising, that one of its working surfaceswill be turned upwards which will cause the centre of gravity G of theshoe to be located in front of the pivot flI-llS 0.

Figs. 2 and 3 show modifications of the shoe or contact piece, accordingto which the thickness of the contact piece decreases towards the rearedge in order to d crease the air resistance.

The parts a and a in Fig. 1 and the corresponding parts a and a in Figs.2 and 8 forming the front and rear edges may be of different materialand thickness from the parts a and a forming the working surfaces.

According to Fig. 1 the centre of gravity G lies in the geometrical axisy-y of the shoe, so that the pivot axis 0 has to be located outside ofthe geometrical axis. According to Fig. 4, however, the pivot axis 0 islocated in the geometrical axis of the shoe and the offsetting of thecentre of gravity G is attained by providing within the shoe a weight 9secured by means of screws.

In the constructions shown in l4l, the shoe assumes, when withdrawn fromthe trolley wire, as shown in Fig. 1 in dotted lines, a verticalposition and is turned into the correct contact position when liftingthe trolley frame is owing solely to the fact that the shaft or axis 0travels along an arc of a circle. As, however, the shoe swings duringits ascent, the arcuate movement of the shaft or axis is not suflicientto insure that the shoe will touch the trolley wire with the right face.In order to obviate this drawback I provide within the shoe as shown in5, one spring 73 or preferably two springs 13 and 13 secured at one endto the shaft 0 and pressing at their free end against the walls of thecontact piece.

One of such springs 1 is sufiicient, if an of."- center balancing weightg of suitable dimensions is arranged within the shoe as shown in Fig. 6.

The springs 13 and T and the eccentric weights of the contact piece orshoe are so balanced that the shoe, when removed from the trolley wire,as shown in dotted lines, will assume a position in which itslongitudinal middle plane coincides with the plane of the trolley frame70.

In Fig. 6 I have shown separate sliding pieces Z) detachably secured othe working faces of the shoe a. As shown in dotted lines at 0 the outeredges of these sliding pieces are preferably bent towards the shoe a.The s iding pieces when worn, may be removed and replaced by new ones.

In the Fig. 7 I have shown a threefaced contact piece or shoe having atriangular cross section and three working faces a a a The boringadapted to receive the spindle 0 is located eccentrically in acylindrical part 7'' to which the metal strips 01' sheets forming (1 anda will work alternately in case the collector travels in direction 2' orin the opposite direction respectively. By turning the cylinder 7, afterhaving removed the screws 7 into a position in which the shaft 0 will belocated in the angle between any other pair of working faces, forexample (1 and a said faces a and (1 will work alternately according tothe travelling direction of the shoe. The triangular shoe may be formedof three parts 9 Q2 and Instead of a balancing weight located within thehollow shoe, a weight 9 arranged on a lever .2 may be used as shown inFig. 8. Lever z is pivoted on the shaft 0 and its swinging angle islimited by abutments h. A spring 7* connecting one edge of the shoe awith the lever 2 secures the position of the shoe shown in dotted linesin Fig. 5, when removed from the trolley wire.

in using a single-faced shoe or contact piece, as shown in Fig. 9, theeccentric balancing weight must act in the position of the trolley framek corresponding to either travelling direction in a manner to lower thefront edge of the shoe. For this purpose the wei 'hted lever z ispivoted at a point an of the trolley frame 70, located beyond the pivotshaft 0 of the shoe. A pin it on the weighted lever .2 works in a slot 8arranged in the vertical axis of symmetry y-y of the flange n. Thefarther the trolley frame 7c is pressed downwards towards its horizontalposition, the greater will be the leverage of the moment of the weight gas the distance of the pivot m from the middle plane ;2 increases. Hencethe turning moment of the resultant R- will be balanced independently ofthe position of frame 70.

Another way to secure this balance, is shown in Fig. 10, according towhich the weighted lever z is connected with a pulley p and the flange nof the shoe a with a pulley p of smaller radius. Both pulleys areconnected by means of a rope e. If the distance of the trolley wire ofrom the trolley base Z decreases, that is to say, if the trolley frameapproaches the horizontal position, the angle w formed by the verticalaxis y, y and the trolley frame In increases. Owing to the differencebetween the radii of pulleys p, and p the difference between angle 'wand the angle 10: formed by the balancing lever e and the trolley frameis increases with the increase of angle 10,.

According to Fig. 11 the springs 7- and 7' connected at one end topoints A A respectively of the single-faced contact piece or shoe a andat the other end to point 0 of lever 7L2 pivoted to the shaft 0 areprovided to balance the turning moment of the resultant R. In order thatlever k may always span the front spring in either direction of travel,for example spring 1 in the direction '5 as shown in Fig. 11, the end 0of lever ]L2 is connected by a rod or rope to a fixed point 0 locatedunderneath and at a distance ft, from the pivot 0 of the tilting trolleyframe 7..', which is greater than the length of lever 7L2, while thelength of frame Z0 added to- [L1 is equal to the length of rod 70 addedto the length of lever k The modification shown in Fig. 12 allows theuse of the device shown in Fig. 11 in connection with pantograph trolleyframes. lVit-h reference to Fig. 12, la, and 1 6 are the upper links ofthe pantograph frame forming its top joint 0 The inclined tilting frame7c is pivoted at its lower end to the top joint- 0 and bears at itsupper end the pivot shaft 0 of the contact piece or shoe a. A guidingbar k connects pivot 0 of the flange n of the shoe a with a guiding linkZ at 0 Guiding link 1: may be provided either ith a weight g as shown indotted lines or may be connected by means of springs 1' and 1' to pointsB and B located either on the links 70 and 70 of the pantograph trolleyor on a trolley base of fixed height if such a one is used.

Having now fully described and ascertained the said invention and themanner in which it is to be performed, I declare, that what I claim is:

1. A current collector, comprising a hollow shoe having at least oneflat contact surface of substantial width for engagement with a sourceof current supply and adapted to travel lengthwise along the same; asupport to which the shoe is pivoted; and means tending to lower thefront edge of the shoe during its travel in either direction.

2. A current collector, comprising a hollow shoe having at least oneflat contact surface of substantial width for engagement with a sourceof current supply and adapted to travel lengthwise along the same; a support to which the shoe is pivoted at one side of its center of gravity;and means tending to lower the front edge of the shoe during its travelin either direction} 3. A current collector, comprising a hollow shoehaving two oppositely-located, fiat counterpart contact surfaces ofsubstantial width for engagement with a source of current supply andadapted to travel length wise along the same alternatively, saidsurfaces having a length considerably greater than their width; and asupport to which the shoe is pivoted between such surfaces.

4. A current collector, comprising a hollow shoe having twooppositely-located, flat counterpart contact surfaces of substantialwidth for engagement with a source of current supply and adapted totravel lengthwise along the same alternatively; a support to which theshoe is pivoted between such surfaces; and means tending to lower thefront edge of the shoe during its travel in either direction.

5. A current collector, comprising a hollow shoe having a long, flatcontact surface of substantial width for engagement with a source ofcurrent supply and adapted to travel lengthwise along the same; asupport whereto the shoe is pivoted; and means for causing said shoe tobear throughout its length against said current source.

6. A current collector, comprising a hollow shoe having a long, fiatcontact surface of substantial width for engagement with a source ofcurrent supply and adapted to travel lengthwise along the same; asupport whereto the shoe is pivoted; and a weight connected to said shoeand tending to lower the front edge thereof during travel.

7. A current collector, comprising a hollow shoe having a long, flatcontact surface of substantial width for engagement with a source ofcurrent supply and adapted to travellengthwise along the same; a supportwhereto the shoe is pivoted; and a weight the posed within and connectedto said shoe and tending to lower the front edge thereof during travel.

8. A current collector, comprising a hollow shoe having a long, flatcontact surface of substantial width for engagement with a source ofcurrent supply and adapted to travel lengthwise along the same; asupport whereto the shoe is pivoted; and a spring associated with saidshoe and tending to hold its contact surface parallel with the shoesuport. p 9. A current collector, comprising a hollow shoe having along, flat contact surface of substantial width for engagement with asource of current supply and adapted to travel lengthwise along thesame; a support whereto the shoe is pivoted; a balancing weight associated with said shoe; and a spring also associated with the shoe andtending to hold its contact surface parallel with the shoe support.

10. A current collector, according to claim 9, in which both the weightand the spring are disposed within the confines of the hollow shoe.

In testimony whereof I aflix my signature.

JULIUS FISCHER DE TOVAROS.

